spinocerebellar ataxia


spi·no·cer·e·bel·lar a·tax·i·a

a generic term now increasingly used to describe autosomal dominant-inherited ataxias that have a progressive course. The terminology is regulated by the human genome organization, and each new gene locus, when found, is indicated by "SCA" followed by a number. Currently, at least 23 distinct types have been reported (SCA1-SCA23). All types closely resemble one another clinically and usually cannot be distinguished by phenotype alone. Pathologically, all types are caused by a variable combination of nerve cell loss in the cerebellum, basis pontis, olivary nuclei, substantia nigra anterior horns, and in the posterior thoracic nucleus. Formerly, diseases in this group were usually labeled "Marie ataxia" or "olivopontocerebellar atrophies." SCA3 is now known as Machado-Joseph disease. Many of these disorders are due to expansions of the CAG sequence in various genes on various chromosomes, including chromosome 3p, 6p, 20p, 5q, 6q, 7q, 8q, 11q, 12q, 15q, 19q, and 22q.

spinocerebellar ataxia

A clinically and genetically heterogeneous group of cerebellar disorders, which is characterised by progressive incoordination of gait and often poor co-ordination of hands, speech and eye movements, due to degeneration of the cerebellum with variable involvement of the brainstem and spinal cord.

spi·no·cer·e·bel·lar a·tax·i·a

(spī'nō-ser'ĕ-bĕl'lăr ă-tak'sē-ă) The most common hereditary ataxia, with onset in middle to late childhood, manifested as limb ataxia, nystagmus, kyphoscoliosis, and pes cavus; the major pathologic changes are found in the posterior columns of the spinal cord.

Pagon,

R.A., Pagon syndrome - anemia from birth (in males); ataxia evident by age 1 year; clonus and positive Babinski sign. Synonym(s): sideroblastic anemia; spinocerebellar ataxia

spi·no·cer·e·bel·lar a·tax·i·a

(spī'nō-ser'ĕ-bĕl'lăr ă-tak'sē-ă) Generic term now increasingly used to describe autosomal dominant-inherited ataxias that have a progressive course.